Running threads at different frequencies on the same core type can’t save energy and extend battery endurance. That’s where 2 core types come in handy.
Energy
There’s more to getting best performance and energy efficiency on Apple silicon. These vary greatly depending on how apps are coded, as shown here.
Looks at power use and energy efficiency in M3 Pro chips, deriving equations for energy use according to numbers of cores used and their role.
How much faster are P cores at running the same thread as E cores, and how much more energy do they require? And how do they compare with using the GPU?
How to interpret various measurements reported in Activity Monitor, from % CPU to Energy Impact, and how they can be compared across different Macs.
Using a test of compressing a 1 GB file with AppleArchive, measurements of power used by core clusters show how efficient using the E cores really is.
Using CPU % or Energy values in Activity Monitor appears to show that running code on E cores is less efficient than on P cores. Don’t believe a word of it.
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